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1.
乙型肝炎患者外周血CD4+ CD25+调节性T细胞表型与功能分析   总被引:18,自引:0,他引:18  
目的 观察急、慢性乙型肝炎(AHB、CHB)患者外周血CD4+CD25 high调节性T细胞(Treg)的频率、表型和功能特点.方法 采集16例AHB急性发病期(发病后第1周)患者、72例CHB患者和32例健康人的外周血,检测Treg频率,并分析其表面CD45RO、CD45RA、HLA-DR、CD95和细胞内细胞毒T淋巴细胞相关抗原4(CTLA-4)的表达水平.应用实时荧光定量RT-PCR检测CD4+ CD25+、CD4+ CD25-、CD4+和CD4-等细胞亚群和外周血单个核细胞(PBMC)的FoxP3 mRNA表达量.通过MACS免疫磁珠分选Treg,并应用[3H]掺入法检测Treg抑制抗-CD3抗体和HBV抗原刺激的PBMC增殖能力,并观察Treg对HBV抗原或抗-CD3抗体刺激自体PBMC分泌IFNγ的影响.结果 CD4+CD25 high Treg高表达CD45RO、HLA-DR、CD95和细胞内CTLA-4,低表达CD45RA,并且较特异的高表达FoxP3 mRNA.乙型肝炎病人外周血Treg频率与健康对照(3.50±0.72)%比较无统计学差异,但CHB组(3.90±1.44)%显著高于AHB组(3.10±0.87)%,P<0.05.Treg本身对于HBV抗原或抗-CD3抗体刺激没有明显的增殖反应和IFNγ分泌,但可抑制自体PBMC增殖和IFNγ分泌,其中对HBV抗原刺激引起的细胞反应抑制作用较强.结论 HBV感染者外周血Treg较特异地表达FoxP3分子,能抑制HBV抗原特异性细胞免疫反应,这对于深入阐明CHB发病机制具有重要意义.  相似文献   

2.
目的 测定HBV感染不同阶段患者外周血CD4+CD25+调节性T细胞(Treg)的频率及标记分子,并分析其与临床指标的相关性.方法 采集79例慢性乙型肝炎(CHB)、12例急性乙型肝炎(AHB)患者、26例无症状HBV携带者(ASC)和20例健康对照的外周血,流式细胞仪分析Treg频率、Treg细胞表面和胞内特征性分子的表达.普通RT-PCR和相对荧光定量PCR测定叉头/翼状转录因子3(Foxp3)在CD25+Treg细胞的表达水平.所有患者及健康对照均经ELISA检测HBV血清标记物水平,实时荧光定量PCR测定血清HBV DNA载量,并进行肝功能检测.结果 总CD4+CD25+T细胞占外周血CD4+T细胞的比率,在各患者组和健康对照组之间差异均无统计学意义(P>0.05).HBeAg阳性CHB组CD4+CD25高表达T细胞频率(3.42%±0.81%)与HBeAg阴性CHB组(3.19%±0.67%)、ASC组(3.05%±0.64%)比较,差异无统计学意义(均P>0.05),但明显高于健康对照组(2.72%±0.71%,P=0.034)和AHB组(2.25%±0.54%,P=0.013).CD4+CD25高表达T细胞表面高表达CD45RO、CD25分子,低表达CD45RA,细胞内高表达细胞毒性T淋巴细胞相关抗原-4(CTLA-4)和Foxp3.各患者组及健康对照组Treg中Foxp3表达水平的差异无统计学意义(P>0.05).CHB组患者的Treg频率与血清病毒载量呈正相关(r=0.48,P=0.018).结论 Treg可能通过抑制T细胞免疫应答反应而影响病毒清除,并与CHB患者的持续感染密切相关.  相似文献   

3.
于建武  孙丽杰  刘伟  康鹏  赵勇华 《肝脏》2012,17(4):237-239
目的 了解胰岛素抵抗的慢性丙型肝炎患者外周血CD4 +CD25+调节性T细胞(Treg)数量和功能的变化.方法 筛选40例HLA-A2+慢性丙型肝炎患者(其中20例合并胰岛素抵抗),流式细胞仪检测患者CD4+CD25+Treg细胞占外周血中CD4+T细胞的频率,液闪计数仪检测对HCV特异性CD8+T细胞增殖的抑制作用,ELISA法检测IFN-y水平.统计学处理采用t检验.结果 胰岛素抵抗的慢性丙型肝炎患者外周血CD4 +CD25+ Treg细胞占CD4+T细胞的(9.5±1.9)%,明显低于慢性丙型肝炎患者的(11.2±2.2)%(t=2.615,P<0.05).胰岛素抵抗指数(HOMA-IR)≥4患者的CD4+CD25+ Treg细胞比例为(9.0±1.8)%,明显低于HOMA-IR<4患者的(10.8±2.3)%(t=2.413,P<0.05).胰岛素抵抗的慢性丙型肝炎患者CD4+CD25+ Treg细胞和去除Treg的外周血单个核细胞(PBMC)共培养上清液中IFN-y为(4 050±580) pg/mL,明显高于慢性丙型肝炎患者的(2 005±330)pg/mL(t=13.705,P<0.01).HOMA-IR≥4患者IFN-y为(5 682±986)pg/mL,明显高于HOMA-IR<4患者的(2 819±660) pg/mL(t=7.630,P<0.01).结论 随着胰岛素抵抗程度加重,慢性丙型肝炎患者外周血CD4+ CD25+ Treg细胞频率减低,对HCV特异性CD8+T细胞增殖的抑制作用减弱.  相似文献   

4.
目的 观察慢性乙型肝炎(CHB)患者应用拉米夫定抗病毒治疗前后外周血T淋巴细胞亚群、CD4+CD25+调节性T淋巴细胞(CD4+CD25+Treg)及IL-10、IFN-γ水平的变化.方法 选择CHB患者90例,在应用拉米夫定抗病毒治疗前及治疗后52周时,用流式细胞仪检测患者外周血T淋巴细胞亚群;在治疗前及治疗后12、24、36、52周时,用流式细胞仪检测外周血CD4+CD25+Treg频率,用双抗体夹心ELISA法检测IL-10、IFN-γ水平.组间及组内总体均数比较采用方差齐性的单因素方差分析或Dunnett's检验,组内治疗前后两时段均数比较采用配对t检验.结果 在90例CHB患者中,完全应答的32例患者的CD4+T淋巴细胞、CD8+T淋巴细胞及CD4+/CD8+较治疗前升高(t=4.055、3.267、2.328,均P<0.05),外周血CD4+CD25+Treg频率在0、12、24、36、52周时分别为(5.40±0.60)%、(4.99±0.59)%、(4.54±0.72)%、(3.86±0.95)%、(3.44±0.76)%;IFN-γ水平、IFN-γ/IL-10逐步上升,IL-10水平逐步下降.部分应答的43例患者的CD4+T淋巴细胞及CD4+/CD8+较治疗前升高(t=3.484、2.018,均P<0.05),CD8+T淋巴细胞较治疗前无明显差异,外周血CD4+CD25+Treg频率在0、12、24、36、52周时分别为(5.65±0.60)%、(5.23±0.63)%、(4.65±0.98)%、(4.42±0.97)%、(4.32±0.82)%,IFN-γ水平、IFN-γ/IL-10升高,IL-10水平降低.无应答的15例患者的外周血CD4+T淋巴细胞、CD8+T淋巴细胞及CD4+/CD8+、外周血CD4+CD25+Treg频率及IFN-y水平、IFN-γ/IL-10、IL-10水平较治疗前无明显变化.结论 应用拉米夫定治疗过程中,获得满意应答的CHB患者的外周血CD4+CD25+Treg频率下降,CD4+/CD8+、IFN-γ/IL-10的比例升高.
Abstract:
Objective To explore the correlation between the efficacy of lamivudine (LAM)therapy and changes of T lymphocyte subsets,CD4+ CD25+ regulatory T lymphocytes (Treg),and levels of interleukin-10 (IL-10)and interferon-gamma (IFN-γ)in the peripheral blood of patients with chronic hepatitis B (CHB).Methods Ninety CHB patients were enrolled in this study.T lymphocyte subsets in the peripheral blood were detected by flow cytometry at baseline and week 52 of LAM therapy.The frequencies of CD4+ CD25+ Treg in the peripheral blood were detected by flow cytometry and levels of IL-10 and IFN-γ were detected by enzyme-linked immunosorbent assay (ELISA)at baseline,week 12,24,36 and 52.The comparisons of overall means between groups and within groups were done by analysis of variance or Dunnett's test.The comparison of means before and after LAM therapy was done by paired t test.Results In 32 complete-responders of 90 CHB patients,the proportions of CD4+ T lymphocytes,CD8+ T lymphocytes and CD4+/CD8+ ratio were increased significantly after LAM therapy (t=4.055、3.267、2.328,all P<0.05); the frequencies of CD4+CD25+ Treg at baseline,week 12,24,36 and 52 were (5.40±0.60)%,(4.99±0.59)%,(4.54± 0.72)%,(3.86±0.95)% and (3.44±0.76)%,respectively; the levels of IFN-γ,IFN-γ/IL-10 ratio were increased,while the IL-10 level was decreased after LAM therapy.In 43 partial-responders,the proportion of CD4+T lymphocytes and ratio of CD4+/CD8+ were increased after LAM therapy (t= 3.484,2.018,both P<0.05); the proportion of CD8+ T lymphocytes was not changed significantly after therapy; the frequencies of CD4+ CD25+ Treg at baseline,week 12,24,36 and 52 were (5.65±0.60)%,(5.23±0.63)%,(4.65±0.98)%,(4.42±0.97)% and (4.32±0.82)%,respectively;IFN-γ level,IFN-γ/IL-10 ratio were increased,while IL-10 level was decreased.In 15 non-responders,the proportion of T lymphocyte subsets,the frequency of CD4+ CD25+ Treg,the levels of IFN-γ and IL-10 were not changed significantly after LAM treatment.Conclusions In CHB patients who have achieved response after LAM therapy,the frequency of CD4+ CD25+ Treg in the peripheral blood is decreased,while ratios of CD4+/CD8+ and IFN-γ/IL-10 in the peripheral blood are increased.  相似文献   

5.
目的 观察外周血CD4 CD25 调节性T细胞(Tregs)百分比和T淋巴细胞亚群在慢性乙型肝炎(CHB)患者中的特点.方法 采集CHB患者15例和健康对照20例的外周血单个核细胞(PBMC)标本,应用三色流式分析法对PBMC中CD4 CD25 Tregs占CD4 百分比及外周血中的T淋巴细胞亚群进行分析.结果 分别比较CD4 CD25highTregs和CD4 CD25 CD127low/-Tregs占CD4 T细胞百分比,两组表型的Tregs在CHB组均高于正常对照组[(4.25%±3.22%vs1.57%±0.64%),(4.39%±2.03%vs1.86%±0.84%)](P<0.01).CHB组外周血中的CD4 T淋巴细胞亚群的百分比(32.28%±6.26%)较正常对照组(39.39%±10.73%)下降,统计学有差别(P<0.05).外周血中CD8 及CD4 /CD8 比值在两组间变化无统计学差异.结论 CHB患者CD4 CD25high和CD4 CD25 CD127low/-Tregs升高,外周血中的CD4 T淋巴细胞百分比下降.  相似文献   

6.
乙型肝炎患者外周血CD4+ CD25+调节性T细胞表型与功能分析   总被引:8,自引:0,他引:8  
目的 观察急、慢性乙型肝炎(AHB、CHB)患者外周血CD4+CD25 high调节性T细胞(Treg)的频率、表型和功能特点.方法 采集16例AHB急性发病期(发病后第1周)患者、72例CHB患者和32例健康人的外周血,检测Treg频率,并分析其表面CD45RO、CD45RA、HLA-DR、CD95和细胞内细胞毒T淋巴细胞相关抗原4(CTLA-4)的表达水平.应用实时荧光定量RT-PCR检测CD4+ CD25+、CD4+ CD25-、CD4+和CD4-等细胞亚群和外周血单个核细胞(PBMC)的FoxP3 mRNA表达量.通过MACS免疫磁珠分选Treg,并应用[3H]掺入法检测Treg抑制抗-CD3抗体和HBV抗原刺激的PBMC增殖能力,并观察Treg对HBV抗原或抗-CD3抗体刺激自体PBMC分泌IFNγ的影响.结果 CD4+CD25 high Treg高表达CD45RO、HLA-DR、CD95和细胞内CTLA-4,低表达CD45RA,并且较特异的高表达FoxP3 mRNA.乙型肝炎病人外周血Treg频率与健康对照(3.50±0.72)%比较无统计学差异,但CHB组(3.90±1.44)%显著高于AHB组(3.10±0.87)%,P<0.05.Treg本身对于HBV抗原或抗-CD3抗体刺激没有明显的增殖反应和IFNγ分泌,但可抑制自体PBMC增殖和IFNγ分泌,其中对HBV抗原刺激引起的细胞反应抑制作用较强.结论 HBV感染者外周血Treg较特异地表达FoxP3分子,能抑制HBV抗原特异性细胞免疫反应,这对于深入阐明CHB发病机制具有重要意义.  相似文献   

7.
目的探讨CD4+CD25+调节性T细胞与慢性HBV感染后不同临床转归和临床特点的相关性。方法在26例慢性乙型肝炎(CHB)患者、15例无症状HBsAg携带者(ASC)和11例肝炎肝硬化(LC)患者和16例正常对照者,分离外周血单个核细胞(PBMC),采用流式细胞仪检测CD4+CD25+调节性T细胞的表达水平。结果CHB组和ASC组的CD4+CD25+调节性T细胞占CD4+T细胞的百分率分别为4.40±2.76%和4.43±2.10%,均高于正常对照组(2.70±0.97%),差异显著(P0.01);CD4+CD25+调节性T细胞的表达水平与HBVDNA水平无相关性(r=0.018,P0.05);在HBeAg阳性与阴性组患者CD4+CD25+调节性T细胞的表达也无明显的差异(P0.05)。结论慢性HBV感染者外周血CD4+CD25+调节性T细胞水平升高,可能与HBV感染的慢性化有关。  相似文献   

8.
目的 探讨乙型肝炎相关肝细胞癌(HCC)患者外周血单个核细胞(PBMC)中HBV不同抗原肽特异性CD3+ CD8+人白细胞抗原( HLA)-A2+细胞的表达.方法 从4例HLA-A2阳性乙型肝炎相关HCC患者外周血中分离PBMC,分别与HBV抗原肽sAg( FLLTRILTI、GLSPTVWLSV、WLSLLVPFV),HBV eore(FLPSDFFPSV)和HBV pol(FLLSLGIHL)及抗-CD3-pacific blue、抗-CD8-异硫氰酸荧光素共育,流式细胞仪分析HBV/HLA-A2-CD3-CD8阳性细胞,克隆培养,筛选出克隆培养的抗HBV T淋巴细胞;再与含有HBV的肝癌细胞株HepG2( HLA-A2+)共育,ELISA法检测其分泌IFN-γ水平.结果 4例患者体内受GLSPTVWLSV肽诱导的特异性抗HBV T淋巴细胞占所有CD8+细胞的1.44%±0.04%,高于FLLTRILTI肽的0.68%±0.08%、FLPSDFFPSV肽的1.06%±0.09%、FLLSLGIHL肽的0.56%±0.04%和WLSLLVPFV肽的0.46%±0.08%(t=0.001,P<0.05).将GLSPTVWLSV/HLA-A2获得的HBV/HLA-A2 PentamerCD3-CD8阳性细胞克隆,获得2株抗HBV CD8 T淋巴细胞,与负荷GLSPTVWLSV肽段的HepG2 (HLA-A2+)细胞共育,CD8 T淋巴细胞分泌较高水平的IFN-γ.结论 乙型肝炎相关HCC患者外周血中存在针对不同HBV抗原肽的特异性抗HBV CD8 T淋巴细胞,其表达量与抗原肽段有关.  相似文献   

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慢性丙型肝炎患者CD4+CD25+调节性T细胞表达增加   总被引:4,自引:0,他引:4  
目的:探讨CD4+CD25+调节性T(Treg)细胞在慢性丙型肝炎患者免疫下调中的意义.方法:流式细胞仪检测慢性丙型肝炎患者外周血中CD4+CD25+Treg细胞的数量;与CD4+CD25-T细胞共同培养,检测其抑制功能;流式细胞仪检测其对CD4+CD25-T细胞合成IFN-γ和IL-4的影响;RT-PCR检测CD4+CD25+Treg细胞中Foxp3的mRNA表达.结果:CD4+CD25+Treg细胞约占慢性丙型肝炎患者外周血中CD4+T细胞的14.1±1.6%,显著高于正常对照5.3±0.8%(P<0.01),显著抑制CD4+T细胞的增殖(P=0.002),以及合成IFN-γ.CD4+CD25+Treg 细胞高表达Foxp3.结论:持续性HCV感染患者CD4+CD25+Treg细胞表达增加,特异性抑制Th1细胞反应.  相似文献   

11.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

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Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.  相似文献   

14.
Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.  相似文献   

15.
Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

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Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the Mr range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [125I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (Ka of 4.7 ± 0.2 × 109 M-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of Mr 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.  相似文献   

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PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.  相似文献   

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